Partial amides of benzene polycarboxylic acids



United States Patent 3,231,607 PARTIAL AMIDES 0F BENZENE POLYCARBOXYLIC ACIDS Bruce W. Hotten, Orinda, Calif., assignor to Chevron Research Company, a corporation of Delaware N0 Drawing. Filed Mar. 29, 1962, Ser. No. 183,376 4 Claims. (Cl. 260-518) This invention pertains to lubricating oil compositions having incorporated therein non-emulsible rust inhibitors. In particular this application is directed to new compounds which are useful in lubricating oil compositions as rust inhibitors where water vapor or water may be present.

The lubricating oil compositions described herein are markedly eifective inhibitors against rust formation. Rust inhibitor which are presently available are used in lubricating oil compositions with varying degrees of success with regard to the elfectiveness of reducing the rust formation. Such rust inhibitors are usually oil-soluble agents which also serve as emulsifying agents to form oilin-water emulsions. For example, the numerous sulfonates and primary amines are oil-soluble rust inhibitors, but they are also effective emulsifying agents. Because these rust inhibitors are oil-soluble and readily emulsifiable in water, water readily Washes the rust protective film from the metal which is to be protected. Furthermore, such agents are not only of doubtful value as rust inhibitors, but the separation of the Water from the oil is made more difficult by their presence.

The non-emulsible rust inhibitor described herein are elfectively used in steam cylinder oils, steam turbine oils, and particularly for other uses where water may be encountered during service.

It is a primary object of this invention to describe new compounds which are effective as rust inhibitors in lubricating oil compositions, rust inhibitors which are particularly effective where water is present.

Therefore, in accordance with this invention, it has been discovered that certain amides of benzene polycarboxylic acids are eifective non-emulsible rust inhibitors in lubricating oil compositions. Thus, the lubricating oil compositions herein contain a base lubricating oil, and incorporated therein, an amide of benzene polycarboxylic acid; that is, the lubricating oil compositions described herein contain rust-inhibiting amounts of amides of benzene polycarboxylic acids.

The amides of benzene polycarboxylic acids used herein as non-emulsible rust inhibitors contain at least two free carboxyl groups and at least one amide group; the amide group being on the carbon atom adjacent to the carbon atom to which a carboxyl radical is attached.

The amides of benzene polycarboxylic acids, that is, benzene polycarboxylic acid amides are of the formula radical); Y is an amide radical such as H O R:

a is a number having a value of at least 2; b is a number having a value of at least 1; the sum of a and b being from 3 to 6, that is a+b=3 to 6; R is an oil-soluble hydrocarbon radical having from 1 to 30 carbon atoms, preferably from 1 to 22 carbon atoms; R is hydrogen or an oil-soluble hydrocarbon radical having from 1 to 30 carbon atoms, preferably from 1 to 22 carbon atoms. When R is a hydrocarbon radical and R is hydrogen, the R radical has a minimum of 10 carbon atoms. When R is an oil-soluble hydrocarbon radical along with R being an oil-soluble hydrocarbon radical the total number of carbon atoms in R and R is no greater than 44 and no less than 12. Preferably, a is 2, b is 1, R is an aliphatic radical, more preferably an alkyl radical, having from 8 to 18 carbon atoms, and R is hydrogen or an aliphatic radical, more preferably an alkyl radical, having from 8 to 18 carbon atoms.

The

radicals are derived from primary or secondary amines containing from 1 to 30 carbon atoms, preferably from 1222 carbon atoms. Such primary and secondary amines are exemplified as follows: decylamine, dodecylamine, tetradecylamine, hexadecyl-amine, octadecylamine, eicosylamine, docosylamine, ethyl decylamine, ethyl dodecylamine, methyl dodecylamine, butyl hexylamine, butyl octylamine, butyl octadecylamine, tetracosylamine, hexacosylamine, triacontylamine, di(dodecyl)amine, di(decyl) amine, decyl dodecylamine, amines derived from soy bean fatty acids, amines derived from coco fatty acids, substituted piperazines having from 1 to 4 carbon atoms substituted thereon, etc.

Lubricating oils which can be used as base oils for the compositions described herein include a wide variety of lubricating oils, such as naphthenic base, parafiin base, and mixed base lubricating oils, other hydrocarbon lubricants, e.g. lubricating oils derived from coal products and the synthetic oil-s, e.g., alkalene polymers (such as polymers of propylene, butylene, etc. and the mixtures thereof), alkylene oxide type polymers, e.g. alkylene oxide type polymers prepared by polymerizing the alkylene oxides, e.g. propylene oxide, etc., in the presence of water or alcohols (e.g., ethyl alcohol), carboxylic acid esters e.g. those which are prepared by esterifying such carboxylic acids as adipic acid, azelaic acid, subaric acid, 'sebacic acid, alkenyl succinic acid, fumaric acid, maleic acid, etc. with the alcohols (such as butyl alcohol, hexyl alcohol, 2-ethylhexyl alcohol, pentaerythritol), liquid esters of acids of phosphorus, alkyl benzenes, polyphenyls (e.g. biphenyls and terphenyls), alkyl biphenyl ethers, polymers of silicon (e.g., tetraethyl silicate, tetraisopropyl silicate, tetra(4-methyl-2-tetraethyl)silicate, hexyl- 4-methyl-2-pentoxy) disiloxane, poly(methyl-2-pentoxy) disiloxane, poly(methyl)siloxane and po1y(rnethylphenyl siloxane) The above base oils may be used individually or in combination thereof, whenever made miscible by the use of solvents.

The rust inhibitors described herein may be incorporated in thickened lubricating oil compositions, includ- Table I hereinbelow illustratesfurther the preparation .of the non-emulsible rust inhibitors .described herein. The anhydride used in these experiments was trimellitic anhydride.

ing lubricating oil compositions thickened to the con- 5 Table I sistency of greases. Such thickening agents include the metal soaps of fatty acids, such as lithium stearate, Sample No 1 2 3 lithium 12-hydroxystearate, etc.; salts of dibasic aciddiamine condensation product. Other thickening agents Anhydride, gramsnn 192 192 192 include polyethylene, the salts of monoamides of ter- 10 ggfiff lifiiiz lil'il 269 ephthalic acids, for example, N-octadecyl-l-ithium ter- See-soy amine? grams ephthalamate, etc. $3 5,333?

Amides of benzene polycarbo rylic acids can be pre- Appearance Tan pared by various methods. The methods by which these amides of polycarboxylic acids are prepared are not a 15 gel? oint range, C 130-145 part of this invention, since there are various means for 01 3 240 150 180 preparing such amides of benzene polycarboxylic acids. Theoretical 2 40 170 160 For example, primary or secondary amines and the benv zene carboxylic acid are blended together, using heat if 2 3 g ig g obtainted g g ea i is pr 110 0 e P1110111 0. an COHSIS S 0 y weig 6X3. ecy 31111119,

necessary to melt the reactants. Usually th deslred- 20 octadecylaminc, 35% octadecenylamiiie; and 45% octadecadienylamme 18 added to a reactlon Vessel and If necessary heat 'l l iis amine was obtained from Armecn 20 which consists of PP thereto to melt Q after which the f octylamine, 9% decylamine, 47% dodecylarnine, 18% tetradecylomine: sired benzene polycarboxyhc acid, or the anhydnde hezmdecylemme, octadeeylamme- It t 1 t ThlS amine was obtamed from Armeen 2S wh1ch cons sts of 20% thereof added i agltatlon- 13 no cm 103 as 0 dihexadecylarnine, dioctadecylamme, dioctadecenylamme, and the order of addition of the reactants. Because the re- 25 dioctadecadlenylammeaction with the anhydrides is exothermlc, a considerable Table II hereinbelow illustrates still further the prepalncrease in temperature is Obtamed, and the t mp r re ration of amides of benzene polycarboxylic acids useful can be thus malntfllned above the meltmg point of the herein as non-emulsible rust inhibitors in lubricating oil reactants untll the reaction 1s complete. The amlnes are compositions using pyromellitic dianhydride.

Table II Sample No 4 5 6 7 8 9 10 11 12 13 Anhydride, grams 109 218 218 109 109 27 41 35 55 Armeen SD, grams 269 Substituted aniline, grams 520 Armeen 20, grams. 764 Armeen 28. grams 530 Armeen 2MT, grams 524 Sec.-dicosy1, docosyl amine, grams 222 Gilsonite amine, grams- 296 300 Hercules rosin amine, grams Duomeen T,4 grams 200 Temperature, 0 130 140 55-120 16 -145 100 95 75-100 1 Time, hours T 1 B 0.5 P1 0.5 0.5 0.5 1 1 1 T W05 an rown as ic Brittle Brittle an axy Appearance Brittle Brittle Tan g Tan Tan B1,?! Brittle Tan Solid Solid Solid Solid Solid Solid Solid il /lett ng polut range, C 125-140 150-170 7176 55 60-70 62-67 50-60 50-70 -150 105415 Found 160 140 100 100 113 82 97 100 Theoretical 150 150 90 90 100 14 0 110 1 This substituted aniline was an aniline containing an alkyl group having 12 carbon atoms.

2 The Gilsonite amines are mixed heterocyclic and other amines derived from the carbonaceous mineral, Gilsouite.

EXAMPLE I A mixture of 222 grams of the secondary amine, eicosyl-docosylamine, and 96 grams of trimellitic anhy- T'dride was heated at 115 C. for one hour to yield a creamy hard'solid having a melting point range of 98- 110 C. The acid number of the product was-found to be (calculated, 180), 7

3 The Hercules rosin amine D is a primary amine consisting primarily of dehydroabietylamine sold by the Hercules Powder 00., Wilmington, Delaware.

4 Duomeen 'I is an N-tallow propylenediamine.

Lubricating oil compositions of the amides of benzene polycarboxylic acids were evaluated as rust inhibitors in lubricating oil compositions as set forth by the data hereinbelow.

Tables III and IV present data obtained in the Humidity Cabinet Test and the HBr Neutralization Test described as follows: 7

HUMIDITY CABINET TEST A sand-blasted steel panel %"X2"x4" was dipped in the oil to be tested, drained of free oil at room temperature, and placed in a humidity cabinet at 120 F. and 100% humidity for the number of hours noted in the tables.

HBr NEUTRALIZAT'ION TEST Three sand-blasted steel panels A3"); 2" x 4" were totally immersed for no more than one second in 0.1% aqueous HBr, and within one second after removing the test panels from the HBr solution, these test panels were dipped in the oil to be evaluated at room temperature. These three panels were dipped and removed from the test oil twelve times during a period of 60 seconds, after which they were suspended in air for four hours at room temperature, then examined for rusting to determine the percent rust occurring thereon.

In the tables hereinbelow, the sample numbers correspond to the sample numbers of Tables I and II hereinabove. In Tables III and IV hereinbelow, the oils being evaluated contained 2% by Weight of the product of the noted sample number. The base oil was a California solvent refined oil.

Table III Sample N 0. Base oil Humidity cabinet test, pe2rcent rust, hours:

Table IV Sample No. Base oil Humidity cabinet test, percent rust, hours:

Table V hereinbelow presents data obtained by evaluating these rust inhibitors in the Turbine Oil Rust Test.

The turbine oil rust test was run by thoroughly mixing 300 ml. of the oil being tested with 30 ml. of distilled water or synthetic sea water at 140 F. A cylindrical steel spinet was immersed therein for 24 hours. Any rust appearing on the spinet and observed by the naked eye was evaluated as a failure for that oil.

amides of benzene polycarboxylic acids as rust inhibitors in grease compositions. The test was the Bearing Protection Test described in Military Specification MILG 3278A.

The base grease consisted of 15% lithium stearate in di(2-ethylhexyl)sebacate.

In addition to the rust inhibitors described herein, the lubricating oil compositions may contain other lubricating oil additives such as oxidation inhibitors, corrosion inhibitors, viscosity index improving agents, detergents, etc.

I claim:

1. The compound (Y)b wherein X is a carboxyl radical, Y is an amide radical of the formula a is a number having a value of at least 2, b is a number having a value of at least 1, the sum of a and b being in the range of 3 to 6, R is an aliphatic hydrocarbon radical containing from 1 to 30 carbon atoms, R is selected from the group consisting of hydrogen and aliphatic hydrocarbon radicals containing from 1 to 30 carbon atoms, and wherein said amide radical is on a benzene carbon atom adjacent to a carbon atom containing a carboxyl group.

2. A compound according to claim 1 wherein R and R are aliphatic radicals of from 12 to 22 carbon atoms.

3. A compound according to claim 1 wherein a is 2, b is 1 and Y is an N,N-dialkylcarboxamide, wherein the alkyl groups are from 8 to 18 carbon atoms.

4. A compound according to claim 1 wherein a is 2, b is 2 and Y is an N,N-dialkylcarboxarnide, wherein the alkyl groups are from 8 to 18 carbon atoms.

References Cited by the Examiner UNITED STATES PATENTS 2,882,230 4/1959 Bartlett et al. 252-33.6 2,924,619 2/1960 Ferstandig 260-518 2,945,813 7/1960 Dreher et al. 25233.6 2,947,781 8/1960 Spiegler 260-518 3,056,832 10/1962 Stromberg 260--518 FOREIGN PATENTS 809,198 2/ 1959 Great Britain.

LORRAINE A. WEINBERGER, Primary Examiner.

JULIUS GREENWALD, LEON ZITVER, Examiners. 

1. THE COMPOUND 